Routing protocols overviewRouter functions are path determination and switching Static addressing Address does not change Dynamic addressing address can change, usually each time computer comes on line RARP,
BOOTP, and DHCP are used to get an IP address for a host to use. RARP often with dumb terminals (hosts with no hard drive) ex: airport reservations Must have RARP server Workstation has his own MAC (burned into his NIC card) Server sends host an IP address to use (until host shuts down, then host repeats process when it restarts) BOOTP host sends broadcast request (unless it knows servers IP address) Must have BOOTP server Server sends host an IP address to use (until host shuts down, then host repeats process when it restarts) BOOTP not really designed for this, uses UDP, is slow DHCP successor to BOOTP, faster, better Can send entire host configuration with subnet mask, in one message Process uses DHCPDISCOVER, DHCPOFFER, DHCPREQUEST, and DHCPACK packets. ARP only gets MAC address, NOT IP address (host has destination IP address) reason for using; source host needs to have both IP and MAC address to send data to destination host makes table – called ARP table DIFFERENCE
BETWEEN ARP and PROXY ARP ARP host sends request for MAC address Destination is on same wire (subnet, segment, etc) and replies with MAC address PROXY ARP host sends request for MAC Destination is NOT on same segment as host Router sends source host his own MAC address Routed protocol ex; IP, IPX (NOVELL), and APPLETALK provides
addressing functions Ex IP addresses multiprotocol routing means router can have several tables, one for each routed protocol Routing protocol routers talk to each other and share route (table) information about the best routes to other networks ex: RIP, IGRP, EIGRP, and OSPF (all these are interior gateway
protocols)
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